Tamiya and other R/C vehicles (not just for Christmas)

seems like LiPo are all the rage, what do the numbers mean? Broadly, are 2S and 3s like outputs they can deliver, and the mah the capacity? And what are “turns” on a motor specification?

2s 3s 4s etc are the number of cells in a lipo. broadly you get 3.6v(ish) per cell. so a 2s lipo is equivalent to a 7.2v NIMH. (the actual peak voltage is a bit higher, due to teh nature of teh Lipo battery, hence teh increased performance)

You`ll need a special charger for a lipo and it should also be a balance charger for multiple cells to stop them exploding!

2s is the max you will likely be able to run on a brushed setup without motor and gear upgrades.

3s and above you need a brushless motor and metal gears and dogbones and potentially other parts (youll find these as they fail!)

the C number is something to do with internal resistance and how much power a lipo can dump at full throttle. and also something to do with charging i think.

Mah is teh capacity of teh battery -> bigger = more run time. bigger also sometimes means bigger battery so get your ruler out if you have tight battery compartment.

or something like that…

Broadly, are 2S and 3s like outputs they can deliver, and the mah the capacity? And what are “turns” on a motor specification?

I’m bound to get this wrong, but I think with Lipos you get 4.2V output per “S”, so 2S = 8.4V, 3S = 12.6V, etc. That compares to 7.2v you’d get out of a ‘standard’ Tamiya style NiMH pack. Yes, Mah = capacity.

I’ve just gone LiPo (though not really run with any of them yet). I does take a fair bit of YouTubing/reading to work it out as it’s not super straight forward and your average charger manual is written in hardcore Engrish.

Motor turns. Essentially; Less turns = faster motor. The turns refer to the wire turns around the rotor. With less turns the wire is a lot thicker. Check your ESC can handle it. Don’t think you are meant to go below 25T with a standard Tamiya TBLE-02 for instance (though I have used a 23T Tamiya RZ motor with no issues in the short term). You also need to check the ESC can handle a lipo if you go that route. Again the standard Tamiya ESC can handle lipo but is not designed to so will not cut out when the voltage drops too low which can knacker the battery. This can be overcome by using a £4 lipo alarm off ebay which attaches to the battery balance lead and bleeps when you get down to a certain level.

Fantastic, thanks all – much to digest in that Roger’s Hobbies link too!

broadly you get 3.6v(ish) per cell.

3.6 is real dead flat you’re killing the battery
3.7 is “nominal” empty
4.2 is full

the C number is something to do with internal resistance and how much power a lipo can dump at full throttle. and also something to do with charging i think.

C gives you the max discharge rate. In terms of capacity. A 2000mAh lipo with a 20C discharge could give you 2A x 20 = 40A max discharge (2000mA = 2A obvs).

The C numbers are usually “optimistic”. If you halve them, they’re more realistic.

3.6 is real dead flat you’re killing the battery

there is loads of chat about this and no real answer about how low you can go. except that at 3.0v per cell the chemistry kicks off and things get exciting!!

I have my lipo alarm go off at 3.4V (as a conservative minimum after much reading around!) and it always trips on acceleration with a resting charge of about 3.7v per cell.

there is obviously a peak draw and voltage drop on hard acceleration but no one seems to know if a short low burst is bad or not. ( realistically i suppose it isnt great!)

if i put my lipo alarm at 3.7V i`d pretty much get no runtime as the cutoff would trip at about 4v resting and it only charges to about 4.2V! the reccommended storage voltage is 3.8V (its what mine were shipped at)

Basically its a minefield of random advice out there!

Yeah, the thing is that 3.4V steady voltage, and a dip to 3.4V while you stall a motor or something, aren’t the same thing so as long as the car’s still moving, so is the target. my Hobbywing esc kindly just doesn’t tell you the numbers, it just has low medium and high, avoids the whole question 🙂

Actually mostly what kills lipos is bad storage and cheap chargers imo. I’ve never hurt one while driving but I have totally killed them by forgetting to disconnect after I finish playing. TBH I think there’s quite a bit of myth/hysteria about them, RC people seem to veer between total trust, and using the cheapest clone chargers on ebay and charging without a bag, and absolute paranoia and assuming that if you don’t handle it with kid gloves it’ll burn your house down.

Meanwhile mountain bikers strap lipos to their heads and throw themselves off precipices.

I run my XV on stock silver can and 3s. I originally thought the silver can will blow up in no time and I will think about what brushless and esc to go for once it happens, but I had over 30 packs through it now and it’s still going strong. I am using the hobbywing 1060 esc which is under £20. The motor gets quite hot though so I have a 40mm fan pointing at it. It is plenty fast enough for me at a stupidly low cost.

Plenty fast at low cost? Sounds good to me, ta! 🙂 Just read that Roger’s Hobbies Lipo guide – holy cow, I’m going nowhere near ’em!

I run one of these Brushless Sensored motors on my TBLE-02S with a standard 7.2v NiMH pack. It is plenty fast enough in a TT02B. Full acceleration will see it squirm about and squirrel off in a random direction. I have another that I daren’t put in a Rising Fighter (it would be bonkers and uncontrollable), a Lunchbox (again, pure wild) or my Fox (1980’s vintage – the gearbox and driveshafts would fail instantly.)

The linked motors could be had for less than £20 last year, so I guess demand is hiking the price a bit.

I so want to get back into RC cars. Mine is just sat staring at me every time I go into the utility room where it is all stored. LiPos have been double bagged in proper LiPo bags in the garage for years so should probably check they’re not about to take out half the garages !

Really fancy pootling around with a scale model and trying to make videos that look realistic energy and physics wise. Think I am broken as the go-pro should really be for bike vids throwing myself down hills. 😀

I’ve broken mine 😭

Sounds like I’ve stripped reverse gear. Also the ESC had come unfixed. I need to have a proper look today at what exactly has gone wrong. It’s a shame as I’d got it running really well after replacing the Tamiya connectors.

After much time away and donating my broken Blackfoot to someone of this Parish I have ordered a Tamiya thing. It arrives tomorrow. I’ll post photos when it built and painted which may be a while.

Had to sell a Lego set or two to fund it but to be honest they just sit there gathering dust. This will get used.

Blimey, Modelsport/UPS don’t hang about. Tracking said tomorrow but it’s just been delivered. Ordered at 11:30am yesterday.

Yeah, kudos to them – ordered an out of stock Delta at the weekend, arrived this morning. 🙂

That’s great service from Modelsport! I’ve used them for a few odds n sods and they’ve always been pretty good.

So, Tamiya Unimog 425 update. It arrived at Xmas and a spent a great few days chucking it together and painting it. When I had the rolling chassis done I obviously sent it around the kitchen a few times and had a bit of an issue with the NSF wheel binding when the wheelnut was done up tight. I just loosened off the wheelnut slightly and thought no more about it.

The first time it was all finished me and the lad took it out in the snow. Spectacular 4 wheel drifts until the steering stopped steering. When I stripped it down it had knackered the servo, ordered a waterproof one with metal gears which has been great ever since.

2nd time out (a couple of weeks later) it was icy snow, we had great fun – until we lost front wheel drive. When I had a look at it, the hub had lost the little retaining pin so the NSF was just spinning.

3rd time out – last weekend – no snow and off to the local pump track. No folk around (obviously) so we had great fun over the jumps. It was a bit too narrow really but some of the crashes were spectacular! Ended up with the NSF wheel off – boo. When I stripped it down last night I found that I’d mixed up the inner hub retaining nuts front and back when I’d first built it up – the rear ones grip into the hub, the front ones don’t. I only realised when I compared the ‘too tight’ side with the ‘just right’ side. Silly error, but it was the cause of the breakdown on the 2nd and 3rd time we played out with it. More destruction testing planned for the 13th when my son’s with us next but I feel loads more confident now I’ve cured the NSF wheel problem properly rather than just curing the symptoms.

As R/Cs are all new to me I feel like I know loads more than I did before Xmas. I feel really pleased with myself that I didn’t bin the instructions when I’d finished building it, they’ve been really useful if only to get the part numbers of the driveshaft retaining pin and wheelnuts so I could stick them into eBay and get replacements ordered.

With all of this new confidence I’ve ordered another kit which should arrive in early March, the 2CV Rallye. I’ve ordered another controller etc too so we’ll be able to race them. I’m betting on the 2CV being quicker (as it’s lighter) but we’ll see.

In the meantime, one of my son’s Xmas pressies was a Volantex Racent Vector SR48 radio speedboat. It was the first time he’s been with me and the boating lake in our village hasn’t been frozen since Xmas so we took it out on Sunday gone. Impressively quick with an impressive amount of water shooting out of the back like a jet ski. Awesome value for £50 complete, just looking to see if I can get a bigger battery for it now.

After much time away and donating my broken Blackfoot to someone of this Parish I have ordered a Tamiya thing. It arrives tomorrow. I’ll post photos when it built and painted which may be a while.

Which will happen first: the Blackfoot reaches it’s destination or you build the new one?

Which will happen first: the Blackfoot reaches it’s destination or you build the new one?

Well I plan on doing it properly so I need to stop playing Xbox, but it’s Thursday so the new Forza Horizon 4 season starts today, which means I could start tomorrow but she’s made plans. You get the idea.

Lockdown depending I think that Blackfoot may get to you at around the same time as I finish it. I hope my radio gear still works.

Right – I’m starting to assemble the bits and pieces I need to complete, and I’ve got some questions. The manual says (or at least suggests) I need:

Instant cement
Synthetic rubber cement
Gel type thread loc
Molybdenum grease
Ceramic grease

Are instant and synthetic rubbber cement different things? Are molybdenum and ceramic grease different things? What’s gel type thread lock? Any recommendations gratefully received – bit worried about getting the wrong thing…

Instant Cement – superglue, or cyanoacrylate glue if you want to be a pedant

For the rest I’d just chuck them into Google with Tamiya or RC in front of them and see what comes up. Does the kit not have little little pots/tubes of grease in with it?

Does the kit not have little little pots/tubes of grease in with it?

It does! 🙂 Didn’t want to open anything until I was ready to assemble, but everything’s so neat*, isn’t it? I thought there was only damper oil in there, but we got two flavours of grease too. 🙂

* Just to expand on that – I was reluctant to open bags as I had a profound fear of getting the approximately 7 million pieces mixed up, but it’s so neatly bagged and labelled, I clearly need to stop being a wuss. Now – any recommendations on where to find an M3 x 0.5mm roll/forming tap, or is it “take a punt on Amazon” time…? 🙂

For the roll tap, I just ordered one off amazon and it was fine. The price gone mad since and it’s out of stock now. Anything is fine as long as it’s the right size and type. It’s only going into plastic. Don’t forget to get a decent tap driver for it though.

Another thing I found is the Tamiya screws go rusty very quickly so I ended up with a set of stainless from rc bearings. It’s a pain to change them all out so I would just go stainless straight away to save having to change them out later.

Threadlock I just go for loctite 248 as it’s neat to use.

There are 2 types of glue you need for the tyres. The tyre insert needs to have the 2 ends stuck together. Contact adhesive is good for that. Tyre to rim is just any superglue.

I would also recommend a thicker diff oil as the one that comes with the kit is too thin for the seals and will leak out after couple of runs. My experience minimum is 10k.

There is a good thread on rccrawler forums on the chassis.

The next thing is probably to look at increasing the ride height as the stock setup will only handle very smooth gravel. It does get quite spendy though.

Gold-dust, thank you! 🙂

@nicholas_yiu did you replace all of them with stainless? On the TT02 there’s around 15 different sizes which would be nearly £30 on screws alone.

Plenty fast at low cost? Sounds good to me, ta! 🙂 Just read that Roger’s Hobbies Lipo guide – holy cow, I’m going nowhere near ’em!

@pondo – the bit with what causes fire at the end is great haha!

i wouldnt be too dismissive though as they do offer a decent upgrade without actually doing or costing too much (upgrade in terms of speed and run time anyway).

i`ve charger that does LIPO and Nimh, runs of 12v car and mains and only cost £25 – its balance, has a charging cut out feature and a charging end alarm. great bit of kit. (the idea is we can take our cars on camping trips)

i`m not worried about lipo death explosions… much.. haha

Yes, I did replaced them all with stainless and yes it was close to £30.

I just cannot stand rusty screws on my car. They are also hex drive which is another reason I went for them.

If you are willing to wait, rcmart does a XV01 titanium screw kit for not much more.

I’m not spending £30 on screws for a £130 kit. I’ve ordered 100 M3x10mm stainless ones off eBay as they are the bulk of the chassis screws on the TT02 and they were only £3.29

When I was building up my Axial SCX10.2 I decided to get a proper set of hex drivers. The screws are small and easy to round, plus it’s nice to have decent tools. I had a pretty decent set already but they come in a big case and I didn’t want to have to carry them around when I’m taking the car out.

I bought some MIP hex drivers, I have to say, they are bloody ace. Very accurately ground tip. Also lobbed a few other bits into a pencil case for when I’m using the buggy or the crawler out and about – tiny knipex wrench, some tweezer style things for grabbing little stones out of the chassis, cable ties, spare R clips etc

Yeah, the difference between quality and cheap tools is even bigger for these than it is for bikes, since every bolt is tiny. (and also more often scraped, or full of mud, and often even on quality rc vehicles the fasteners are pretty cheap and nasty- axial’s little dome heads are pish frinstance.

But RC Tax is even higher than Bike Tax so so I’ve ended up with a complete set of nice makita screwdriver and allen bits, some bondhus t-handles, a little teng ratchet…

I now know why tweezers are recommended.

😁

Nice! Get tweezers. 🙂

@Merak

That is really nice. My only complaint would be it’s pre-painted body and it being 4wd.

Why couldn’t Tamiya do it with a M06 with a clear body shell?

Oh wait, a bit of google says you can buy the body unpainted coupled with a modified M06 chassis for off road…

You are giving me ideas, very expensive ideas:

https://www.djm-motorsport.co.uk/mkii_escort_mcrae.html

Only had a light dusting where I am, but enough to have some fun in the XV-01:

1st pack was the most fun I had for a while. Something wasn’t quite right when I got to my second pack, it was like I had a sticky throttle as in the power don’t kick in till about 1/2 a second in. Maybe the electrics got a bit wet, or maybe the silver can finally on its way out. I suppose it’s not designed to take punishment from 3S batteries.

The aftermath:

Note how the snow at the front melted from the heat of the motor

Re the LIPO worries. I know more modellers who have lost their garage/workshops due to their aging beer fridge catching fire than through LIPO charging accidents.

Mega – can’t wait till mine’s built. But at the same time, I’m enjoying the build itself way, way more than I thought I would – it’s gonna take me ages because I’m desperately trying to do it right, but I’m really enjoying it! 🙂

Snow Tiger.

Waiting for a Panther G to come in to stock. Found a place in Europe that does them for 70% of UK prices and they have a greater range of models available.

How did you get the Escort ahead of April ?

Jadlam are showing the Escort in stock – nothing at Modelsport

That tank looks great in the snow!

Wireless Madness are also showing stock for the Escort too.

How did you get the Escort ahead of April ?

I pre ordered it last year.

I want a tank so bad.😬